Many types of integrated circuits have internal circuit blocks that generate analog signals. Information about analog signals generated by internal circuit blocks of an integrated circuit can be used for debugging and production testing. Some of the nodes of internal circuit blocks of an integrated circuit can be forced to specific voltages for testing and debugging purposes.
An integrated circuit may have an analog test bus that is used to test internal analog signals. An analog signal is provided from an internal circuit block in the integrated circuit through an analog test bus to external measurement equipment that is used to measure the analog signal. However, this measurement technique has limited accuracy, limited bandwidth, and typically requires a long test time.